This invention relates to machines for counting and stacking flexible articles and more particularly to such machines for counting and stacking newspapers being delivered from a printing and assembling operation in an overlapped conveyor stream. The ever increasing speeds of newspaper printing presses have placed demanding requirements upon the efficiency, reliability and operating speeds of the associated newspaper handling apparatus, particularly that apparatus employed in the mailroom sections of printing plants where the individual papers are stacked, bundled and dispatched to waiting trucks for ultimate delivery to the subscriber.
The wedge shape of newspapers due to their folded edge limits the number of papers that may be contained in a stable, free-standing stack. To provide stacks of greater numbers of papers it is necessary to compensate for the wedge shape by forming stacks of two or more batches wherein the folded edges of each batch are displaced 180.degree.. To accomplish this, the counter-stacker machine must rotate its stack receiving table 180.degree. between batch deliveries thereto. The operating time for such rotation is dependent upon the batch delivery time which in turn is dependent upon stacking time for the predetermined number of papers which is ultimately dictated by the press speed and rate at which papers are delivered therefrom. In addition to rotating the table between batch deliveries, the counter-stacker machine must also be capable of dispatching its stack in an equal period of time to permit the next batch to be delivered.
At modern press speeds, the rotating and ejecting speeds of the counter-stacker serve to provide unsettling forces upon the stack, thereby requiring particular attention to the support of the stack during such operations. The tables have been provided with front and rear vertical guide plates, and movable gates have been provided at the ends of such plates for restraining the ends of the stack during rotation. The ejector means customarily are chain driven bars which sweep across the table to eject the stack. Such ejector bars must be positioned out of the rotational path of the table during indexing thereof, and therefor must travel a certain distance before engaging the stack when they are operated. Moreover, operation of the gates and ejector mechanisms must be positively correlated to prevent damage to the machine. Each of the foregoing serve to reduce operating cycle time and efficiency of the machine.